/**
 * Copyright (C) 2015 ogaclejapan
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.zwy.kutils.widget.tab_viewpager.main;

import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.view.animation.Interpolator;

public abstract class SmartTabIndicationInterpolator {

  public static final SmartTabIndicationInterpolator SMART = new SmartIndicationInterpolator();
  public static final SmartTabIndicationInterpolator LINEAR = new LinearIndicationInterpolator();

  static final int ID_SMART = 0;
  static final int ID_LINEAR = 1;

  public static SmartTabIndicationInterpolator of(int id) {
    switch (id) {
      case ID_SMART:
        return SMART;
      case ID_LINEAR:
        return LINEAR;
      default:
        throw new IllegalArgumentException("Unknown id: " + id);
    }
  }

  public abstract float getLeftEdge(float offset);

  public abstract float getRightEdge(float offset);

  public float getThickness(float offset) {
    return 1f; //Always the same thickness by default
  }

  public static class SmartIndicationInterpolator extends SmartTabIndicationInterpolator {

    private static final float DEFAULT_INDICATOR_INTERPOLATION_FACTOR = 3.0f;

    private final Interpolator leftEdgeInterpolator;
    private final Interpolator rightEdgeInterpolator;

    public SmartIndicationInterpolator() {
      this(DEFAULT_INDICATOR_INTERPOLATION_FACTOR);
    }

    public SmartIndicationInterpolator(float factor) {
      leftEdgeInterpolator = new AccelerateInterpolator(factor);
      rightEdgeInterpolator = new DecelerateInterpolator(factor);
    }

    @Override
    public float getLeftEdge(float offset) {
      return leftEdgeInterpolator.getInterpolation(offset);
    }

    @Override
    public float getRightEdge(float offset) {
      return rightEdgeInterpolator.getInterpolation(offset);
    }

    @Override
    public float getThickness(float offset) {
      return 1f / (1.0f - getLeftEdge(offset) + getRightEdge(offset));
    }

  }

  public static class LinearIndicationInterpolator extends SmartTabIndicationInterpolator {

    @Override
    public float getLeftEdge(float offset) {
      return offset;
    }

    @Override
    public float getRightEdge(float offset) {
      return offset;
    }

  }
}
